Adolph cohn



ADOLPH COI-IN, OF NEW YORK, N. Y.

ALLOY.

No Drawing.

To all whom it may concern:

Be it known that I, ADOLPII Conn, a citizen of the United States, and aresident of the borough of Manhattan, city, county, and State of NewYork, have invented certain new and useful Improvements in Alloys, ofwhich the following is a specification.

This invention relates to a new alloy of precious metals and its objectis to provide a novel and comparatively inexpensive way of hardeningplatinum for the purpose of rendering it suitable for use in jewelry'orfor any other desired reason.

It is of course well known that pure platinum is too soft to resist wearand various expedients have been resorted to with varying degrees ofsuccess, for the purpose of overcoming this difliculty.

I have discovered that the addition of a very small proportion 9f goldhas the desired hardening effect. A decided hardening of platinum isattained by the addition of as little as 1% of gold. It ismy presentbelief that no more than 15% of gold in a given amount of alloy is everneeded for this purpose. While I do not intend to limit myself in thisparticular, but as an exemplification of my invention, I have found bySpecification of Letters Patent.

Application filed. May 2, 1

Patented Dec. 2, 1919.

919. Serial No. 294,183.

scleroscope tests that an alloyof 95 9/0 plati num and 5% gold is equalin hardness to a 10% iridiuiii-platinum alloy.

Another advantage of the use of gold as a hardening agency forplatinum-is that these two metals alloy readily and form a perfectlyhomogeneous and permanent mixture. These metals form an alloy which willnot tarnish. They also form analloy which is more easily soldered thanis either pure platinum or iridio-platinum, and Which has suflicientductility to be wrought cold or 'hot, and is also capable of beingrepeatedly melted without destroying its character.

I am aware of the fact that gold which has less than half of thehardness of platinum, has had its hardness increased by the addition ofa small percentage of platinum, but believe that it is new to increasethe hardness of platinum by the addition of a comparatively smallquantity of a softer metal such as gold.

What I claim is:

An alloy of platinum and gold with the gold from 1% to 15% of the whole.

In witness whereof I have hereunto set my hand this 1st day of May,1919.

- ADOLPH COHN.

